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bioRxiv · 10.1101/2023.07.21.550025

Nucleotide-protocell interactions: A reciprocal relationship in prebiotically pertinent environments

Deshpande, K.·Mulewar, S. S.·Rajamani, S.
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Abstract

Spontaneous interactions between nucleotides and lipid membranes are likely to have played a prominent role in the emergence of life on Earth. However, the effect of nucleotides on the physicochemical properties of model protocellular membranes is relatively less understood. To this end, we aimed to discern the effect of canonical nucleotides on the properties of single-chain amphiphile membranes under prebiotically relevant conditions of multiple wet-dry cycles. Furthermore, the change in critical aggregation concentration of the membranes, and their stability in the presence of nucleotides, was also investigated in Astrobiologically analogue environments. We report that different nucleotides, lipid headgroups, and the ionic makeup of the system affect lipid-nucleotide interactions, which in turn can modulate the effect of nucleotides on the membranes. Specifically, oleic acid membranes seemingly showed an increase in the critical aggregation concentration, and an increase in the stability against prebiotically relevant selection pressures, in the presence of certain nucleotides. Our work has implications for understanding how nucleotides might have shaped the protocellular landscape of the prebiotic Earth.

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Deshpande, K., Mulewar, S. S., Rajamani, S.. 2023-07-21. Nucleotide-protocell interactions: A reciprocal relationship in prebiotically pertinent environments. https://doi.org/10.1101/2023.07.21.550025

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